Device for preventing film movement in cameras

ABSTRACT

A camera for roll film perforated at predetermined metering intervals includes a transport mechanism for advancing the film along an exposure plane and a metering mechanism having an inactive condition and an active condition for stopping film transport when the film is correctly positioned for exposure. A film sensing pawl is mounted for movement between a retracted position resting on the film surface, an extended position transversing the film while in a film perforation and a metering position spaced from the extended position in the direction of film advancement. A resilient force is selectively applied to the sensing member in a direction urging the sensing member from its metering position toward its extended position. The force on the sensing member is relieved at least during operation of the camera&#39;&#39;s exposure mechanism so that the force is not transmitted by the sensing member to the filmstrip.

United States-; Patent [1 91 Ettischer et a]. v A

[ DEv lcE FOR PREVENTING FILM MOVEMENT IN CAMERAS [75] Inventors: I Helmut Ettischer, Ruit; Wolfgang Ort, Stuttgart-Bad; Horst Simon, 1 Fellbach; Kurt Steisslinger,' Stuttgart, all of Germany [73] Assigneezo Eastman Kodak Company, Rochester, N.Y,

22 Filed: Aug,.21, 1972 21 Appl. No.: 282,631

52 U.S.Cl ..'..95/31FM 51 lnt.Cl....; G03b 19/04 [58] FieldofSearch 95/31 [56] v References Ci ted UNITED STATES PATENTS 3,709,128 1/1973 Beach Q s/31PM [451 Nov. 27,1973

Primary Examiner-John M. Horan Attorney-W. H. J. Kline et a1.

' [57 ABSTRACT A camera for roll film perforated at predetermined metering intervals includes a transport mechanism for advancing the film along an exposure plane and a metering mechanism having an inactive condition and an active condition for stopping film transport when the film is correctly'positioned for exposure. A film sensing pawl is mounted for'movement between a re- I *tracted position restingon' the film surface, an extended position transversing the film while in a film perforation and a metering position spaced from the extended position in "the direction of film advancement. A resilient force is selectively applied to the sensing member inf a direction urging the sensing member from its metering position toward its extended position. The force on the sensing member is relieved at least during operation, of the cameras exposure mechanism so that the force is not transmitted by the sensing member to the filmstrip.

r 7 Claims, 4 Drawing Figures 11.22 \IZO" exposure period.

DEvIcEroR PREV NTING-FILM MOVEMENT IN I CAMERAS CROSS-REFERENCE TO RELATED APPLICATION Reference is made to commonly-assigned, copendin'g U. S. Pat. application Ser. No; 203,524,;entitled FILM METERING .MECI-IANISMS FOR CAMERAS, and

filed Dec. 1, 1971 in'the name of David E. Beach., BACKGROUNDJOF THE INVENTION 1. Field of the lnvention The present invention relates to cameras having" means'for detecting the presenceof a film perforation to selectively lock and release the film transport mechanism, and more particularly to such cameras having means for minimizing any surge of force from the detecting means on the film during an exposure interval.

2. Description of the Prior Art The'present invention is an improvement over cameras of theitype disclosedin copending, coassigned U.

S. Pat. application Ser. No.203,524, entitled Film Metering Mechanism For Cameras filed Dec. 1, 1 971. i in the name of David E. Beach. In the camera therein disclosed, a metering lever is movable between'an inactive position and an active position disablingthe cam-- eras film transport mechanism. A film sensing pawl is mounted for movement from a'retractedpo'sition engaging the film surface through an extendedposition transversing the film whenintercepting one of the film perforations to a metering position spaced from, the ex- 2 ment of the invention presented" below, reference is made to the accompanying drawings, in which:

FIG. 1 is a view of a portion of a camera in accordance with the present inventionand showing a cartridge containing afilm striploaded in the camera, the camera elements being shown in their. positions immediately following an exposure,

DESCRIPTION OFTHE PREFERRED EMBODIMENT r Because cameras are well known, the present description will be directed in particular to elements forming part of, or cooperating more directly with apparatus in accordance with the present invention. It is to be understood that camera elements not specifically 7 shown or described may take various forms well known to those skilled in the art. y

Referring to the drawings, a camera having a housing 10 has been shown with a filmcartridge 1 2 received tended position in the direction of film advancement by I the trialing edge of the perforation'as the film is advanced- The film sensing pawl and the metering lever are associated such that the metering lever is moved to itsactive position uponmovement of the. sensing pawl to its metering position. A spring urges the sensing pawl I from its metering position toward its extended position and, since the metering pawl remains in the film perforation during exposure, the spring force is applied also to the trailing edgeofthe film perforation. Thisforce on the film is opposed byfrictional forces between camera" elements and between the film and camera and/or cartridge surfaces. When the shutter is tripped, minor vibrations travel through the camera. Thesevibrations may relieve static friction wherever'it occurs within the camera. Loss of frictional forces restraining the'film can cause the spring force on the film from the pawl to move the film during exposure.

SUMMARY OF THE INVENTION It is, an object of the present invention to reduce or eliminate the possibility of film movement during the exposure period by eliminating the force of the film sensing pawl on the trailing edge'of the film perforation during a picture-take operation when the camera vibra tions can suddenly relieve frictional restraints.

In a preferred embodiment of the present invention,

I this object has been accomplished by physicallyremoving the spring which applies'the force to the film sensing pawl fromcontact withthe sensing pawl during the The invention, and its objects, and advantages, will become moreapparen't-in the detailed description of the preferred embodiment presented below.

BRIEF DESCRIPTION OF THE DRAWINGS In the detailed description of the preferred emboditherein. The film'cartridge has supply and take-up chambers 14 and 16, respectively, which enter corresponding supply, and take-up compartments in the camera housing. A filmstrip 18 is carried by the cartridge and is perforated along one edge at predetermined metering intervals. The cartridge may contain opaque backing paper, and may be of the type shown in coassigned U. S. Pat. No.3,l38,0 8 l which issued on June 23, 1964.to I-Iubert Nerwin.

A film advance slide 20 is mounted in camera housing 10 so as to be movable from the position shown in FIG. 1 in the direction of arrow 22-. Slide 20 has an opening24 with a cam surface, 26 formed thereby, a plurality of ratchet teeth 28 and a lug 30. A spring 32 urgesslide 20 tothe right as viewed in FIG. 1.

A shutter device member 34 is rotatably carried on a stud 36 in housing 10 and is biased in a clockwise direction as viewed in FIG. 1 by a spring 38. An arm 40 on drive member 34 actuates ashutter, not shown, dur-v ing clockwise rotation of the drive member to effect an exposure. A second arm 42 of the drive member has a camfollower 44 extending into opening 24 of slide 20 to follow cam surface 26 during leftward movement of the slide, thereby rotating drive member 34 in a counterclockwisedirection against the force of spring 38. Thefunction of twoother amIs 46 and 48 on drive member 34 will be explained hereinafter. v

A rack 50, having a plurality of gearteeth 52, is slidably mounted in housing l0an'd is urged by a spring 54 into contact with a. stud 56' on drive member 34. Teeth 552 mesh withcorresponding gear teeth on a'gear sector 58 which, through gears60 and 62, advances film from supply compartment 14 to take-up compartment 16 when rack 50 is moved to the left. Gear sector 58 is connected to gear 60' thru a one-way clutch so that gears 60 and 62 do not turn when the right. I Y

A latch member is: pivotally mounted in housing 10 on a stud 66 for movement betweena latch position (retaining drive member 34 in its cocked position;

rack 50 is moved to 3 FIGS. 2-4) and a release position (permitting spring 38 torapidly move the drive member to its uncooked position as shown in' FIG. l). v An intermediate member 70 is rotatably carried in housing 10 on a stud 72 andis biased in a clockwise direction by a spring 74. Member 70 has three arms 76-78 and-three tabs 80-82 respectively on the end of those arms. I 1 I A film sensing member 84 is rotatably and slidably carried by a pin 86 which extends into slot 88 in the sensing member. A film sensing pawl 100 n the sensing member extends toward film 18 at the-cameras exposure plane. A leaf spring 102 tends to rotate the senstridge. As the film advances, when a pe foration rack 50 to the left to advance film from supply com;

partment 14 to take-up, compartment 16 of the carreaches the position of film sensing pawl 100, the pawl ing member in a clockwise direction to urge sensing paw] 100 to a film transversing position asshown in FIG. 1. A cam surface l04 and a tab106 are provided on the other end of the sensing member, and the functions of these elements will be'explained hereinafter.

A control member 108 is rotatably carried by astud 110 and is urged in a counterclockwise direction by a spring 112 against a stop 114 on the camera housing. The upper portion of control lever 108 is positioned in the region of (Sam surface 104 of sensing member 84, while the lower portion of the control lever has tab 1 16 which lies in the path of a claw 118 which is rotatably carried by a stud 120 on slide 20 and which is urged'in a clockwise direction about the stud by a spring 122 until leg 124 of the'claw engages follower 44- of shutter drive lever 34. A wire spring 126 is aligned with a pin 128 on sensing member 84. Y. Operation is moved into the perforation by spring 102 so that the sensing member is moved to the leftby the advancing film. Note that at this time there is no spring force opposing such movement of the sensing member since spring 126 has been removedfrom pin 128 by spring 112.

At the moment that the next succeeding frame of film reaches the cameras exposure station, tab 106 on sensing member 84 falls off the tab 82 of intermediate member 70, enabling spring74 to rotate the intermediate member in a clockwise direction until tab 81 on .arm 77 engages ratchet teeth 28 on slide 20 to prevent further'film advancement. When the operator releases slide 20, it is retumed to the right by" spring 32. The camera elements are now positioned as showninlFlG. 4 and the camera is ready to be operated to make an exposure. Note that spring 126 is spaced from pin 128 so that there is no force on the sensing member tending 7 FIG. 1 shows the camera elements positioned after an rection against the force of spring 38 until arm 48 thereon snaps behind latch member 64.'At.the same time, claw 118 engages tab 116 on control lever'l08 to rotate the control lever in a clockwise direction, whereby the upper portion of the control leverengages camsurface 104 of film sensing member 84 to rotate the film sensing member, in a counterclockwise direc tion withdrawing sensing pawl 100 from the film perforation; As control member 108 continues to rotate, spring 126 engages pin 128 to move sensing member 84 to the right until tab 106 thereon falls beneath tab 82 on intermediate member 70.

During the first stroke of slide 20, lug 30 misses rack 50 because the rack has been held in its lower FIG. 1 position by pin 56 on drive member 34. Therefore, during the first movement of the slide, there is no film advancement. The camera elements are now positioned as shown in FIG. 2, and, as the operator allows spring 32 to return slide 20 to the right, rack 50 is raised by pivotedin a clockwise direction by spring 122 until it a is no longer aligned with tab 116 of control member 108.

to move the'se'nsing member-to'the right. Thus, when the shutter is tripped and camera vibrations are set up, there is no load on the film sensing pawl which might cause film movement toward the cameras supply chamber due to the'loss of frictional resistance mentioned above. a

To make an exposure, latch 64 is rotated in a clockwise direction (by the cameras body release lever, not shown), releasing drive member 34 to rundown in a clockwise direction from its FIG. 1 positionto operate the shutter mechanism by its arm 40. During such running down movement of drive member-34, itsarm 46 engages tab on arm 76 of intermediate member 70 to rotate the intermediate member in a counterclockwise direction, thereby removing tab-81 from ratchet teeth 28 of slide 20. At the same. time, arm 42 of the drive-member. pivots claw 118 in a counterclockwise direction to align the right end of the claw with tab 116 of-controllever 108, and pin 56 on the drive member moves'rack 50 out of alignment with'abutment 30 on the slide; Spring 1.02 retains sensing, pawl in' the film perforation. The camera elements are now in their respective positions shown in FIG-1,ahd the camera is ready to be operated to advance the next succeeding film frame to the exposure station as hereinbefore described. a

The invention has been described in detail with particular reference to a preferred embodiment, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

We claim:

1. In a camera having (1) supply and take-up chambers for receiving respectively supply and take up rolls of a filmstrip perforated at predetermined metering intervals; (2) transport means'operable toadvance a received filmstrip along a camera exposure plane from said supply chamber, tosaid take-up chamber, (3) an exposure mechanism operable to effect the exposure of received filmstrip atthe exposure plane; (4) a metering mechanism having an active condition disabling said transport means and any inactive condition, (5)'a film sensing member movable from a retracted position on one side of said'exposure plane to an extended position transversing said exposure plane when intercepting one of the perforations of a received filmstrip, and, by the termined position. p 1

4. The improvementas defined in claim 3 wherein 1 trailing edge of theperforation as the received filmstrip is advanced, to a metering position spaced from said extended position in the general direction of filmstrip advancement; (6 means associated withsaid sensing member and said metering mechanism for placing said metering mechanism in its active condition upon movement of said sensing memberto its metering position; and (7) means for applying a force tosaid sensing member, said force having a direction urging said sens ing member from its metering position toward its extended position; the improvement comprising means associatedwith said force applying means for selec; tively removing said force from said sensing member at least during operation of saidtexposure mechanism, whereby such force is not transmitted by said sensing member to a received filmstrip duringexposure.

2. In a camera having (1) supply and take-up chamsaid sensing member contac table by said control member. v v i v 5. The improvement as defined inclaim 2 further comprising means associated with said control member and said transport means for moving said control member from its predetermined position upon intial operaw tion of said transport means.

bersfor receiving respectively supply and take-up rolls trailing edge .of the perforation as the received filmstrip 6. The improvement as defined in claim 2 further I comprising spring means for urging said sensing member from its retracted position towardits extended position. v

"7. In a camera having (1) supply and take-up chambers for receiving respectively supply and take-uprolls of filmstrip perforated at predetermined metering intervals; (2) transport means operable to advance a received filmstrip along a camera exposure plane from saidsupply'chamber to said take-up chamber; (3) a shutter mechanism movable from a cocked position to a'run-down position to effect the exposure 'of received filmstrip at the exposure plane; (4) cocking means op erable' to move said shutter mechanism to its'cocked position; (5) a metering mechanism having an active condition disabling said transport means and an inacis advanced to a metering position spacedfrorn said extended position in the general directionof filmstrip advancement; and (6) means associated with said sens ing member and said metering mechanism for placing said metering mechanismtin its active condition upon movement of said sensing member to its metering position; the improvement comprising: i 7 means, including a control member movable toward and away from a predetermined position, for moving said sensing member in a direction along the exposure plane opposed to the direction of film ad vancement only when said control member is moved away from its predetermined position; and

means for locating said control member at its prede termined position at least during operation of said 1 exposure mechanism, 3. The improvement as defined comprising means associated with said sensing member and said control member for moving said sensing memher from its metering position to its retracted position in'cIaimZfurther b I v v means for movingsaid control member to its predeupon movement of said control member from its prede-' said last-mentioned means includes a cam surface on tive condition; (6)v a film sensing member movable from a retracted position on one side of said exposure plane to an extended position transversing said exposure plane when intercepting one of the perforations of a received filmstrip, and, by the trailing edge of the perforation-as the received filmstrip is advanced, to a me tering position spaced from said'extended position in the general direction of filmstrip advancement; and (7) meansassociated with said sensing member and said metering mechanism for placing said metering mechanism in. its active condition upon movement of said sensing member to its metering position; the improvement comprising:

a control member movable toward and away from a predetermined position; i spring means associated with said control member in a manner to be operatively coupled to said sensing member for urging said sensing member in a direction along the exposure plane opposed to the direction of film advancement when said control memher is moved awayfrom its predetermined position and to be uncoupled from said sensing member when said control member is inits predetermined position; A

I r tennined position v I at least during run-down movement of said shutter mechanism; and

- means associated withsaidcocking means for rnov-' r ing said-control member from its determinedlposition upon operation of saidcocking means. v

Pb-4050- VUNITEDYSTATES PATENT OFFICE CERTIFICATE, OF CORRECTION "P -mtNo.3.774.5;3 I b ueL vmh n 1 m 155mm 921;! "Letters 'Pat-ent are hereby corrected .as shown below:

Itiizentofle) I: is fcerti fied ti hatferror appears in the above-identified ba tent f 1 "Front Page; "'-"'Foreign Application Priqrity. Date. I

; (SEAL) Att'est;

A t estin g Officer e Commissioner 6f Patents f woctober n 'mi Germany i 3- 1 1 Signed azjd; isealld tlfii s' 17th day of Spfemfir 1974.

MccdYiM.'-clssofi Jig X MARSHALL DANNl 3 3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION.

Patent No- 3.774.513 D t N vpmhm 97 1972 Elgtischer. Ort. Simnn and St'ei Q5] ingnr It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

[30] Front Page, -Foreign Application Priority Data October E 971 Germany G 71 38 893 7-- Signed and sealed this 17th day of September 1974.

(SEAL) Attes.t=

McCOY M. GIBSON JR; C. MARSHALL DANN Attesting Officer Commissioner of Patents 

1. In a camera having (1) supply and take-up chambers for receiving respectively supply and take-up rolls of a filmstrip perforated at predetermined metering intervals; (2) transport means operable to advance a received filmstrip along a camera exposure plane from said supply chamber to said take-up chamber, (3) an exposure mechanism operable to effect the exposure of received filmstrip at the exposure plane; (4) a metering mechanism having an active condition disabling said transport means and an inactive condition, (5) a film sensing member movable from a retracted position on one side of said exposure plane to an extended position transversing said exposure plane when intercepting one of the perforations of a received filmstrip, and, by the trailing edge of the perforation as the received filmstrip is advanced, to a metering position spaced from said extended position in the general direction of filmstrip advancement; (6) means associated with said sensing member and said metering mechanism for placing said metering mechanism in its active condition upon movement of said sensing member to its metering position; and (7) means for applying a force to said sensing member, said force having a direction urging said sensing member from its metering position toward its extended position; the improvement comprising means associated with said force applying means for selectively removing said force from said sensing member at least during operation of said exposure mechanism, whereby such force is not transmitted by said sensing member to a received filmstrip during exposure.
 2. In a camera having (1) supply and take-up chambers for receiving respectively supply and take-up rolls of a filmstrip perforated at predetermined metering intervals; (2) transport means operable to advance a received filmstrip along a camera exposure from said supply chamber to said take-up chamber; (3) an exposure mechanism operable to effect the exposure of received filmstrip at the exposUre plane; (4) a metering mechanism having an active condition disabling said transport means and an inactive condition, (5) a film sensing member movable from a retracted position on one side of said exposure plane to an extended position transversing said exposure plane when intercepting one of the perforations of a received filmstrip, and, by the trailing edge of the perforation as the received filmstrip is advanced, to a metering position spaced from said extended position in the general direction of filmstrip advancement; and (6) means associated with said sensing member and said metering mechanism for placing said metering mechanism in its active condition upon movement of said sensing member to its metering position; the improvement comprising: means, including a control member movable toward and away from a predetermined position, for moving said sensing member in a direction along the exposure plane opposed to the direction of film advancement only when said control member is moved away from its predetermined position; and means for locating said control member at its predetermined position at least during operation of said exposure mechanism.
 3. The improvement as defined in claim 2 further comprising means associated with said sensing member and said control member for moving said sensing member from its metering position to its retracted position upon movement of said control member from its predetermined position.
 4. The improvement as defined in claim 3 wherein said last-mentioned means includes a cam surface on said sensing member contactable by said control member.
 5. The improvement as defined in claim 2 further comprising means associated with said control member and said transport means for moving said control member from its predetermined position upon intial operation of said transport means.
 6. The improvement as defined in claim 2 further comprising spring means for urging said sensing member from its retracted position toward its extended position.
 7. In a camera having (1) supply and take-up chambers for receiving respectively supply and take-up rolls of filmstrip perforated at predetermined metering intervals; (2) transport means operable to advance a received filmstrip along a camera exposure plane from said supply chamber to said take-up chamber; (3) a shutter mechanism movable from a cocked position to a run-down position to effect the exposure of received filmstrip at the exposure plane; (4) cocking means operable to move said shutter mechanism to its cocked position; (5) a metering mechanism having an active condition disabling said transport means and an inactive condition; (6) a film sensing member movable from a retracted position on one side of said exposure plane to an extended position transversing said exposure plane when intercepting one of the perforations of a received filmstrip, and, by the trailing edge of the perforation as the received filmstrip is advanced, to a metering position spaced from said extended position in the general direction of filmstrip advancement; and (7) means associated with said sensing member and said metering mechanism for placing said metering mechanism in its active condition upon movement of said sensing member to its metering position; the improvement comprising: a control member movable toward and away from a predetermined position; spring means associated with said control member in a manner to be operatively coupled to said sensing member for urging said sensing member in a direction along the exposure plane opposed to the direction of film advancement when said control member is moved away from its predetermined position and to be uncoupled from said sensing member when said control member is in its predetermined position; means for moving said control member to its predetermined position at least during run-down movement of said shutter mechanism; and means associated with said cocking means for moving Said control member from its determined position upon operation of said cocking means. 